user.c

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/*-------------------------------------------------------------------------
 *
 * user.c
 *    Commands for manipulating roles (formerly called users).
 *
 * Portions Copyright (c) 1996-2022, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * src/backend/commands/user.c
 *
 *-------------------------------------------------------------------------
 */
#include "postgres.h"
 
#include "access/genam.h"
#include "access/htup_details.h"
#include "access/table.h"
#include "access/xact.h"
#include "catalog/binary_upgrade.h"
#include "catalog/catalog.h"
#include "catalog/dependency.h"
#include "catalog/indexing.h"
#include "catalog/objectaccess.h"
#include "catalog/pg_auth_members.h"
#include "catalog/pg_authid.h"
#include "catalog/pg_database.h"
#include "catalog/pg_db_role_setting.h"
#include "commands/comment.h"
#include "commands/dbcommands.h"
#include "commands/defrem.h"
#include "commands/seclabel.h"
#include "commands/user.h"
#include "libpq/crypt.h"
#include "miscadmin.h"
#include "storage/lmgr.h"
#include "utils/acl.h"
#include "utils/builtins.h"
#include "utils/catcache.h"
#include "utils/fmgroids.h"
#include "utils/syscache.h"
#include "utils/timestamp.h"
 
/*
 * Removing a role grant - or the admin option on it - might recurse to
 * dependent grants. We use these values to reason about what would need to
 * be done in such cases.
 *
 * RRG_NOOP indicates a grant that would not need to be altered by the
 * operation.
 *
 * RRG_REMOVE_ADMIN_OPTION indicates a grant that would need to have
 * admin_option set to false by the operation.
 *
 * Similarly, RRG_REMOVE_INHERIT_OPTION and RRG_REMOVE_SET_OPTION indicate
 * grants that would need to have the corresponding options set to false.
 *
 * RRG_DELETE_GRANT indicates a grant that would need to be removed entirely
 * by the operation.
 */
typedef enum
{
    RRG_NOOP,
    RRG_REMOVE_ADMIN_OPTION,
    RRG_REMOVE_INHERIT_OPTION,
    RRG_REMOVE_SET_OPTION,
    RRG_DELETE_GRANT
} RevokeRoleGrantAction;
 
/* Potentially set by pg_upgrade_support functions */
Oid         binary_upgrade_next_pg_authid_oid = InvalidOid;
 
typedef struct
{
    unsigned    specified;
    bool        admin;
    bool        inherit;
    bool        set;
} GrantRoleOptions;
 
#define GRANT_ROLE_SPECIFIED_ADMIN          0x0001
#define GRANT_ROLE_SPECIFIED_INHERIT        0x0002
#define GRANT_ROLE_SPECIFIED_SET            0x0004
 
/* GUC parameter */
int         Password_encryption = PASSWORD_TYPE_SCRAM_SHA_256;
 
/* Hook to check passwords in CreateRole() and AlterRole() */
check_password_hook_type check_password_hook = NULL;
 
static void AddRoleMems(const char *rolename, Oid roleid,
                        List *memberSpecs, List *memberIds,
                        Oid grantorId, GrantRoleOptions *popt);
static void DelRoleMems(const char *rolename, Oid roleid,
                        List *memberSpecs, List *memberIds,
                        Oid grantorId, GrantRoleOptions *popt,
                        DropBehavior behavior);
static Oid  check_role_grantor(Oid currentUserId, Oid roleid, Oid grantorId,
                               bool is_grant);
static RevokeRoleGrantAction *initialize_revoke_actions(CatCList *memlist);
static bool plan_single_revoke(CatCList *memlist,
                               RevokeRoleGrantAction *actions,
                               Oid member, Oid grantor,
                               GrantRoleOptions *popt,
                               DropBehavior behavior);
static void plan_member_revoke(CatCList *memlist,
                               RevokeRoleGrantAction *actions, Oid member);
static void plan_recursive_revoke(CatCList *memlist,
                                  RevokeRoleGrantAction *actions,
                                  int index,
                                  bool revoke_admin_option_only,
                                  DropBehavior behavior);
static void InitGrantRoleOptions(GrantRoleOptions *popt);
 
 
/* Check if current user has createrole privileges */
static bool
have_createrole_privilege(void)
{
    return has_createrole_privilege(GetUserId());
}
 
 
/*
 * CREATE ROLE
 */
Oid
CreateRole(ParseState *pstate, CreateRoleStmt *stmt)
{
    Relation    pg_authid_rel;
    TupleDesc   pg_authid_dsc;
    HeapTuple   tuple;
    Datum       new_record[Natts_pg_authid] = {0};
    bool        new_record_nulls[Natts_pg_authid] = {0};
    Oid         roleid;
    ListCell   *item;
    ListCell   *option;
    char       *password = NULL;    /* user password */
    bool        issuper = false;    /* Make the user a superuser? */
    bool        inherit = true; /* Auto inherit privileges? */
    bool        createrole = false; /* Can this user create roles? */
    bool        createdb = false;   /* Can the user create databases? */
    bool        canlogin = false;   /* Can this user login? */
    bool        isreplication = false;  /* Is this a replication role? */
    bool        bypassrls = false;  /* Is this a row security enabled role? */
    int         connlimit = -1; /* maximum connections allowed */
    List       *addroleto = NIL;    /* roles to make this a member of */
    List       *rolemembers = NIL;  /* roles to be members of this role */
    List       *adminmembers = NIL; /* roles to be admins of this role */
    char       *validUntil = NULL;  /* time the login is valid until */
    Datum       validUntil_datum;   /* same, as timestamptz Datum */
    bool        validUntil_null;
    DefElem    *dpassword = NULL;
    DefElem    *dissuper = NULL;
    DefElem    *dinherit = NULL;
    DefElem    *dcreaterole = NULL;
    DefElem    *dcreatedb = NULL;
    DefElem    *dcanlogin = NULL;
    DefElem    *disreplication = NULL;
    DefElem    *dconnlimit = NULL;
    DefElem    *daddroleto = NULL;
    DefElem    *drolemembers = NULL;
    DefElem    *dadminmembers = NULL;
    DefElem    *dvalidUntil = NULL;
    DefElem    *dbypassRLS = NULL;
    GrantRoleOptions    popt;
 
    /* The defaults can vary depending on the original statement type */
    switch (stmt->stmt_type)
    {
        case ROLESTMT_ROLE:
            break;
        case ROLESTMT_USER:
            canlogin = true;
            /* may eventually want inherit to default to false here */
            break;
        case ROLESTMT_GROUP:
            break;
    }
 
    /* Extract options from the statement node tree */
    foreach(option, stmt->options)
    {
        DefElem    *defel = (DefElem *) lfirst(option);
 
        if (strcmp(defel->defname, "password") == 0)
        {
            if (dpassword)
                errorConflictingDefElem(defel, pstate);
            dpassword = defel;
        }
        else if (strcmp(defel->defname, "sysid") == 0)
        {
            ereport(NOTICE,
                    (errmsg("SYSID can no longer be specified")));
        }
        else if (strcmp(defel->defname, "superuser") == 0)
        {
            if (dissuper)
                errorConflictingDefElem(defel, pstate);
            dissuper = defel;
        }
        else if (strcmp(defel->defname, "inherit") == 0)
        {
            if (dinherit)
                errorConflictingDefElem(defel, pstate);
            dinherit = defel;
        }
        else if (strcmp(defel->defname, "createrole") == 0)
        {
            if (dcreaterole)
                errorConflictingDefElem(defel, pstate);
            dcreaterole = defel;
        }
        else if (strcmp(defel->defname, "createdb") == 0)
        {
            if (dcreatedb)
                errorConflictingDefElem(defel, pstate);
            dcreatedb = defel;
        }
        else if (strcmp(defel->defname, "canlogin") == 0)
        {
            if (dcanlogin)
                errorConflictingDefElem(defel, pstate);
            dcanlogin = defel;
        }
        else if (strcmp(defel->defname, "isreplication") == 0)
        {
            if (disreplication)
                errorConflictingDefElem(defel, pstate);
            disreplication = defel;
        }
        else if (strcmp(defel->defname, "connectionlimit") == 0)
        {
            if (dconnlimit)
                errorConflictingDefElem(defel, pstate);
            dconnlimit = defel;
        }
        else if (strcmp(defel->defname, "addroleto") == 0)
        {
            if (daddroleto)
                errorConflictingDefElem(defel, pstate);
            daddroleto = defel;
        }
        else if (strcmp(defel->defname, "rolemembers") == 0)
        {
            if (drolemembers)
                errorConflictingDefElem(defel, pstate);
            drolemembers = defel;
        }
        else if (strcmp(defel->defname, "adminmembers") == 0)
        {
            if (dadminmembers)
                errorConflictingDefElem(defel, pstate);
            dadminmembers = defel;
        }
        else if (strcmp(defel->defname, "validUntil") == 0)
        {
            if (dvalidUntil)
                errorConflictingDefElem(defel, pstate);
            dvalidUntil = defel;
        }
        else if (strcmp(defel->defname, "bypassrls") == 0)
        {
            if (dbypassRLS)
                errorConflictingDefElem(defel, pstate);
            dbypassRLS = defel;
        }
        else
            elog(ERROR, "option \"%s\" not recognized",
                 defel->defname);
    }
 
    if (dpassword && dpassword->arg)
        password = strVal(dpassword->arg);
    if (dissuper)
        issuper = boolVal(dissuper->arg);
    if (dinherit)
        inherit = boolVal(dinherit->arg);
    if (dcreaterole)
        createrole = boolVal(dcreaterole->arg);
    if (dcreatedb)
        createdb = boolVal(dcreatedb->arg);
    if (dcanlogin)
        canlogin = boolVal(dcanlogin->arg);
    if (disreplication)
        isreplication = boolVal(disreplication->arg);
    if (dconnlimit)
    {
        connlimit = intVal(dconnlimit->arg);
        if (connlimit < -1)
            ereport(ERROR,
                    (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                     errmsg("invalid connection limit: %d", connlimit)));
    }
    if (daddroleto)
        addroleto = (List *) daddroleto->arg;
    if (drolemembers)
        rolemembers = (List *) drolemembers->arg;
    if (dadminmembers)
        adminmembers = (List *) dadminmembers->arg;
    if (dvalidUntil)
        validUntil = strVal(dvalidUntil->arg);
    if (dbypassRLS)
        bypassrls = boolVal(dbypassRLS->arg);
 
    /* Check some permissions first */
    if (issuper)
    {
        if (!superuser())
            ereport(ERROR,
                    (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                     errmsg("must be superuser to create superusers")));
    }
    else if (isreplication)
    {
        if (!superuser())
            ereport(ERROR,
                    (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                     errmsg("must be superuser to create replication users")));
    }
    else if (bypassrls)
    {
        if (!superuser())
            ereport(ERROR,
                    (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                     errmsg("must be superuser to create bypassrls users")));
    }
    else
    {
        if (!have_createrole_privilege())
            ereport(ERROR,
                    (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                     errmsg("permission denied to create role")));
    }
 
    /*
     * Check that the user is not trying to create a role in the reserved
     * "pg_" namespace.
     */
    if (IsReservedName(stmt->role))
        ereport(ERROR,
                (errcode(ERRCODE_RESERVED_NAME),
                 errmsg("role name \"%s\" is reserved",
                        stmt->role),
                 errdetail("Role names starting with \"pg_\" are reserved.")));
 
    /*
     * If built with appropriate switch, whine when regression-testing
     * conventions for role names are violated.
     */
#ifdef ENFORCE_REGRESSION_TEST_NAME_RESTRICTIONS
    if (strncmp(stmt->role, "regress_", 8) != 0)
        elog(WARNING, "roles created by regression test cases should have names starting with \"regress_\"");
#endif
 
    /*
     * Check the pg_authid relation to be certain the role doesn't already
     * exist.
     */
    pg_authid_rel = table_open(AuthIdRelationId, RowExclusiveLock);
    pg_authid_dsc = RelationGetDescr(pg_authid_rel);
 
    if (OidIsValid(get_role_oid(stmt->role, true)))
        ereport(ERROR,
                (errcode(ERRCODE_DUPLICATE_OBJECT),
                 errmsg("role \"%s\" already exists",
                        stmt->role)));
 
    /* Convert validuntil to internal form */
    if (validUntil)
    {
        validUntil_datum = DirectFunctionCall3(timestamptz_in,
                                               CStringGetDatum(validUntil),
                                               ObjectIdGetDatum(InvalidOid),
                                               Int32GetDatum(-1));
        validUntil_null = false;
    }
    else
    {
        validUntil_datum = (Datum) 0;
        validUntil_null = true;
    }
 
    /*
     * Call the password checking hook if there is one defined
     */
    if (check_password_hook && password)
        (*check_password_hook) (stmt->role,
                                password,
                                get_password_type(password),
                                validUntil_datum,
                                validUntil_null);
 
    /*
     * Build a tuple to insert
     */
    new_record[Anum_pg_authid_rolname - 1] =
        DirectFunctionCall1(namein, CStringGetDatum(stmt->role));
    new_record[Anum_pg_authid_rolsuper - 1] = BoolGetDatum(issuper);
    new_record[Anum_pg_authid_rolinherit - 1] = BoolGetDatum(inherit);
    new_record[Anum_pg_authid_rolcreaterole - 1] = BoolGetDatum(createrole);
    new_record[Anum_pg_authid_rolcreatedb - 1] = BoolGetDatum(createdb);
    new_record[Anum_pg_authid_rolcanlogin - 1] = BoolGetDatum(canlogin);
    new_record[Anum_pg_authid_rolreplication - 1] = BoolGetDatum(isreplication);
    new_record[Anum_pg_authid_rolconnlimit - 1] = Int32GetDatum(connlimit);
 
    if (password)
    {
        char       *shadow_pass;
        const char *logdetail = NULL;
 
        /*
         * Don't allow an empty password. Libpq treats an empty password the
         * same as no password at all, and won't even try to authenticate. But
         * other clients might, so allowing it would be confusing. By clearing
         * the password when an empty string is specified, the account is
         * consistently locked for all clients.
         *
         * Note that this only covers passwords stored in the database itself.
         * There are also checks in the authentication code, to forbid an
         * empty password from being used with authentication methods that
         * fetch the password from an external system, like LDAP or PAM.
         */
        if (password[0] == '\0' ||
            plain_crypt_verify(stmt->role, password, "", &logdetail) == STATUS_OK)
        {
            ereport(NOTICE,
                    (errmsg("empty string is not a valid password, clearing password")));
            new_record_nulls[Anum_pg_authid_rolpassword - 1] = true;
        }
        else
        {
            /* Encrypt the password to the requested format. */
            shadow_pass = encrypt_password(Password_encryption, stmt->role,
                                           password);
            new_record[Anum_pg_authid_rolpassword - 1] =
                CStringGetTextDatum(shadow_pass);
        }
    }
    else
        new_record_nulls[Anum_pg_authid_rolpassword - 1] = true;
 
    new_record[Anum_pg_authid_rolvaliduntil - 1] = validUntil_datum;
    new_record_nulls[Anum_pg_authid_rolvaliduntil - 1] = validUntil_null;
 
    new_record[Anum_pg_authid_rolbypassrls - 1] = BoolGetDatum(bypassrls);
 
    /*
     * pg_largeobject_metadata contains pg_authid.oid's, so we use the
     * binary-upgrade override.
     */
    if (IsBinaryUpgrade)
    {
        if (!OidIsValid(binary_upgrade_next_pg_authid_oid))
            ereport(ERROR,
                    (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                     errmsg("pg_authid OID value not set when in binary upgrade mode")));
 
        roleid = binary_upgrade_next_pg_authid_oid;
        binary_upgrade_next_pg_authid_oid = InvalidOid;
    }
    else
    {
        roleid = GetNewOidWithIndex(pg_authid_rel, AuthIdOidIndexId,
                                    Anum_pg_authid_oid);
    }
 
    new_record[Anum_pg_authid_oid - 1] = ObjectIdGetDatum(roleid);
 
    tuple = heap_form_tuple(pg_authid_dsc, new_record, new_record_nulls);
 
    /*
     * Insert new record in the pg_authid table
     */
    CatalogTupleInsert(pg_authid_rel, tuple);
 
    /*
     * Advance command counter so we can see new record; else tests in
     * AddRoleMems may fail.
     */
    if (addroleto || adminmembers || rolemembers)
        CommandCounterIncrement();
 
    /* Default grant. */
    InitGrantRoleOptions(&popt);
 
    /*
     * Add the new role to the specified existing roles.
     */
    if (addroleto)
    {
        RoleSpec   *thisrole = makeNode(RoleSpec);
        List       *thisrole_list = list_make1(thisrole);
        List       *thisrole_oidlist = list_make1_oid(roleid);
 
        thisrole->roletype = ROLESPEC_CSTRING;
        thisrole->rolename = stmt->role;
        thisrole->location = -1;
 
        foreach(item, addroleto)
        {
            RoleSpec   *oldrole = lfirst(item);
            HeapTuple   oldroletup = get_rolespec_tuple(oldrole);
            Form_pg_authid oldroleform = (Form_pg_authid) GETSTRUCT(oldroletup);
            Oid         oldroleid = oldroleform->oid;
            char       *oldrolename = NameStr(oldroleform->rolname);
 
            AddRoleMems(oldrolename, oldroleid,
                        thisrole_list,
                        thisrole_oidlist,
                        InvalidOid, &popt);
 
            ReleaseSysCache(oldroletup);
        }
    }
 
    /*
     * Add the specified members to this new role. adminmembers get the admin
     * option, rolemembers don't.
     */
    AddRoleMems(stmt->role, roleid,
                rolemembers, roleSpecsToIds(rolemembers),
                InvalidOid, &popt);
    popt.specified |= GRANT_ROLE_SPECIFIED_ADMIN;
    popt.admin = true;
    AddRoleMems(stmt->role, roleid,
                adminmembers, roleSpecsToIds(adminmembers),
                InvalidOid, &popt);
 
    /* Post creation hook for new role */
    InvokeObjectPostCreateHook(AuthIdRelationId, roleid, 0);
 
    /*
     * Close pg_authid, but keep lock till commit.
     */
    table_close(pg_authid_rel, NoLock);
 
    return roleid;
}
 
 
/*
 * ALTER ROLE
 *
 * Note: the rolemembers option accepted here is intended to support the
 * backwards-compatible ALTER GROUP syntax.  Although it will work to say
 * "ALTER ROLE role ROLE rolenames", we don't document it.
 */
Oid
AlterRole(ParseState *pstate, AlterRoleStmt *stmt)
{
    Datum       new_record[Natts_pg_authid] = {0};
    bool        new_record_nulls[Natts_pg_authid] = {0};
    bool        new_record_repl[Natts_pg_authid] = {0};
    Relation    pg_authid_rel;
    TupleDesc   pg_authid_dsc;
    HeapTuple   tuple,
                new_tuple;
    Form_pg_authid authform;
    ListCell   *option;
    char       *rolename;
    char       *password = NULL;    /* user password */
    int         connlimit = -1; /* maximum connections allowed */
    char       *validUntil = NULL;  /* time the login is valid until */
    Datum       validUntil_datum;   /* same, as timestamptz Datum */
    bool        validUntil_null;
    DefElem    *dpassword = NULL;
    DefElem    *dissuper = NULL;
    DefElem    *dinherit = NULL;
    DefElem    *dcreaterole = NULL;
    DefElem    *dcreatedb = NULL;
    DefElem    *dcanlogin = NULL;
    DefElem    *disreplication = NULL;
    DefElem    *dconnlimit = NULL;
    DefElem    *drolemembers = NULL;
    DefElem    *dvalidUntil = NULL;
    DefElem    *dbypassRLS = NULL;
    Oid         roleid;
    GrantRoleOptions    popt;
 
    check_rolespec_name(stmt->role,
                        _("Cannot alter reserved roles."));
 
    /* Extract options from the statement node tree */
    foreach(option, stmt->options)
    {
        DefElem    *defel = (DefElem *) lfirst(option);
 
        if (strcmp(defel->defname, "password") == 0)
        {
            if (dpassword)
                errorConflictingDefElem(defel, pstate);
            dpassword = defel;
        }
        else if (strcmp(defel->defname, "superuser") == 0)
        {
            if (dissuper)
                errorConflictingDefElem(defel, pstate);
            dissuper = defel;
        }
        else if (strcmp(defel->defname, "inherit") == 0)
        {
            if (dinherit)
                errorConflictingDefElem(defel, pstate);
            dinherit = defel;
        }
        else if (strcmp(defel->defname, "createrole") == 0)
        {
            if (dcreaterole)
                errorConflictingDefElem(defel, pstate);
            dcreaterole = defel;
        }
        else if (strcmp(defel->defname, "createdb") == 0)
        {
            if (dcreatedb)
                errorConflictingDefElem(defel, pstate);
            dcreatedb = defel;
        }
        else if (strcmp(defel->defname, "canlogin") == 0)
        {
            if (dcanlogin)
                errorConflictingDefElem(defel, pstate);
            dcanlogin = defel;
        }
        else if (strcmp(defel->defname, "isreplication") == 0)
        {
            if (disreplication)
                errorConflictingDefElem(defel, pstate);
            disreplication = defel;
        }
        else if (strcmp(defel->defname, "connectionlimit") == 0)
        {
            if (dconnlimit)
                errorConflictingDefElem(defel, pstate);
            dconnlimit = defel;
        }
        else if (strcmp(defel->defname, "rolemembers") == 0 &&
                 stmt->action != 0)
        {
            if (drolemembers)
                errorConflictingDefElem(defel, pstate);
            drolemembers = defel;
        }
        else if (strcmp(defel->defname, "validUntil") == 0)
        {
            if (dvalidUntil)
                errorConflictingDefElem(defel, pstate);
            dvalidUntil = defel;
        }
        else if (strcmp(defel->defname, "bypassrls") == 0)
        {
            if (dbypassRLS)
                errorConflictingDefElem(defel, pstate);
            dbypassRLS = defel;
        }
        else
            elog(ERROR, "option \"%s\" not recognized",
                 defel->defname);
    }
 
    if (dpassword && dpassword->arg)
        password = strVal(dpassword->arg);
    if (dconnlimit)
    {
        connlimit = intVal(dconnlimit->arg);
        if (connlimit < -1)
            ereport(ERROR,
                    (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                     errmsg("invalid connection limit: %d", connlimit)));
    }
    if (dvalidUntil)
        validUntil = strVal(dvalidUntil->arg);
 
    /*
     * Scan the pg_authid relation to be certain the user exists.
     */
    pg_authid_rel = table_open(AuthIdRelationId, RowExclusiveLock);
    pg_authid_dsc = RelationGetDescr(pg_authid_rel);
 
    tuple = get_rolespec_tuple(stmt->role);
    authform = (Form_pg_authid) GETSTRUCT(tuple);
    rolename = pstrdup(NameStr(authform->rolname));
    roleid = authform->oid;
 
    /*
     * To mess with a superuser or replication role in any way you gotta be
     * superuser.  We also insist on superuser to change the BYPASSRLS
     * property.  Otherwise, if you don't have createrole, you're only allowed
     * to (1) change your own password or (2) add members to a role for which
     * you have ADMIN OPTION.
     */
    if (authform->rolsuper || dissuper)
    {
        if (!superuser())
            ereport(ERROR,
                    (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                     errmsg("must be superuser to alter superuser roles or change superuser attribute")));
    }
    else if (authform->rolreplication || disreplication)
    {
        if (!superuser())
            ereport(ERROR,
                    (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                     errmsg("must be superuser to alter replication roles or change replication attribute")));
    }
    else if (dbypassRLS)
    {
        if (!superuser())
            ereport(ERROR,
                    (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                     errmsg("must be superuser to change bypassrls attribute")));
    }
    else if (!have_createrole_privilege())
    {
        /* things you certainly can't do without CREATEROLE */
        if (dinherit || dcreaterole || dcreatedb || dcanlogin || dconnlimit ||
            dvalidUntil)
            ereport(ERROR,
                    (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                     errmsg("permission denied")));
 
        /* without CREATEROLE, can only change your own password */
        if (dpassword && roleid != GetUserId())
            ereport(ERROR,
                    (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                     errmsg("must have CREATEROLE privilege to change another user's password")));
 
        /* without CREATEROLE, can only add members to roles you admin */
        if (drolemembers && !is_admin_of_role(GetUserId(), roleid))
            ereport(ERROR,
                    (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                     errmsg("must have admin option on role \"%s\" to add members",
                            rolename)));
    }
 
    /* Convert validuntil to internal form */
    if (dvalidUntil)
    {
        validUntil_datum = DirectFunctionCall3(timestamptz_in,
                                               CStringGetDatum(validUntil),
                                               ObjectIdGetDatum(InvalidOid),
                                               Int32GetDatum(-1));
        validUntil_null = false;
    }
    else
    {
        /* fetch existing setting in case hook needs it */
        validUntil_datum = SysCacheGetAttr(AUTHNAME, tuple,
                                           Anum_pg_authid_rolvaliduntil,
                                           &validUntil_null);
    }
 
    /*
     * Call the password checking hook if there is one defined
     */
    if (check_password_hook && password)
        (*check_password_hook) (rolename,
                                password,
                                get_password_type(password),
                                validUntil_datum,
                                validUntil_null);
 
    /*
     * Build an updated tuple, perusing the information just obtained
     */
 
    /*
     * issuper/createrole/etc
     */
    if (dissuper)
    {
        bool    should_be_super = boolVal(dissuper->arg);
 
        if (!should_be_super && roleid == BOOTSTRAP_SUPERUSERID)
            ereport(ERROR,
                    (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                     errmsg("permission denied: bootstrap user must be superuser")));
 
        new_record[Anum_pg_authid_rolsuper - 1] = BoolGetDatum(should_be_super);
        new_record_repl[Anum_pg_authid_rolsuper - 1] = true;
    }
 
    if (dinherit)
    {
        new_record[Anum_pg_authid_rolinherit - 1] = BoolGetDatum(boolVal(dinherit->arg));
        new_record_repl[Anum_pg_authid_rolinherit - 1] = true;
    }
 
    if (dcreaterole)
    {
        new_record[Anum_pg_authid_rolcreaterole - 1] = BoolGetDatum(boolVal(dcreaterole->arg));
        new_record_repl[Anum_pg_authid_rolcreaterole - 1] = true;
    }
 
    if (dcreatedb)
    {
        new_record[Anum_pg_authid_rolcreatedb - 1] = BoolGetDatum(boolVal(dcreatedb->arg));
        new_record_repl[Anum_pg_authid_rolcreatedb - 1] = true;
    }
 
    if (dcanlogin)
    {
        new_record[Anum_pg_authid_rolcanlogin - 1] = BoolGetDatum(boolVal(dcanlogin->arg));
        new_record_repl[Anum_pg_authid_rolcanlogin - 1] = true;
    }
 
    if (disreplication)
    {
        new_record[Anum_pg_authid_rolreplication - 1] = BoolGetDatum(boolVal(disreplication->arg));
        new_record_repl[Anum_pg_authid_rolreplication - 1] = true;
    }
 
    if (dconnlimit)
    {
        new_record[Anum_pg_authid_rolconnlimit - 1] = Int32GetDatum(connlimit);
        new_record_repl[Anum_pg_authid_rolconnlimit - 1] = true;
    }
 
    /* password */
    if (password)
    {
        char       *shadow_pass;
        const char *logdetail = NULL;
 
        /* Like in CREATE USER, don't allow an empty password. */
        if (password[0] == '\0' ||
            plain_crypt_verify(rolename, password, "", &logdetail) == STATUS_OK)
        {
            ereport(NOTICE,
                    (errmsg("empty string is not a valid password, clearing password")));
            new_record_nulls[Anum_pg_authid_rolpassword - 1] = true;
        }
        else
        {
            /* Encrypt the password to the requested format. */
            shadow_pass = encrypt_password(Password_encryption, rolename,
                                           password);
            new_record[Anum_pg_authid_rolpassword - 1] =
                CStringGetTextDatum(shadow_pass);
        }
        new_record_repl[Anum_pg_authid_rolpassword - 1] = true;
    }
 
    /* unset password */
    if (dpassword && dpassword->arg == NULL)
    {
        new_record_repl[Anum_pg_authid_rolpassword - 1] = true;
        new_record_nulls[Anum_pg_authid_rolpassword - 1] = true;
    }
 
    /* valid until */
    new_record[Anum_pg_authid_rolvaliduntil - 1] = validUntil_datum;
    new_record_nulls[Anum_pg_authid_rolvaliduntil - 1] = validUntil_null;
    new_record_repl[Anum_pg_authid_rolvaliduntil - 1] = true;
 
    if (dbypassRLS)
    {
        new_record[Anum_pg_authid_rolbypassrls - 1] = BoolGetDatum(boolVal(dbypassRLS->arg));
        new_record_repl[Anum_pg_authid_rolbypassrls - 1] = true;
    }
 
    new_tuple = heap_modify_tuple(tuple, pg_authid_dsc, new_record,
                                  new_record_nulls, new_record_repl);
    CatalogTupleUpdate(pg_authid_rel, &tuple->t_self, new_tuple);
 
    InvokeObjectPostAlterHook(AuthIdRelationId, roleid, 0);
 
    ReleaseSysCache(tuple);
    heap_freetuple(new_tuple);
 
    InitGrantRoleOptions(&popt);
 
    /*
     * Advance command counter so we can see new record; else tests in
     * AddRoleMems may fail.
     */
    if (drolemembers)
    {
        List       *rolemembers = (List *) drolemembers->arg;
 
        CommandCounterIncrement();
 
        if (stmt->action == +1) /* add members to role */
            AddRoleMems(rolename, roleid,
                        rolemembers, roleSpecsToIds(rolemembers),
                        InvalidOid, &popt);
        else if (stmt->action == -1)    /* drop members from role */
            DelRoleMems(rolename, roleid,
                        rolemembers, roleSpecsToIds(rolemembers),
                        InvalidOid, &popt, DROP_RESTRICT);
    }
 
    /*
     * Close pg_authid, but keep lock till commit.
     */
    table_close(pg_authid_rel, NoLock);
 
    return roleid;
}
 
 
/*
 * ALTER ROLE ... SET
 */
Oid
AlterRoleSet(AlterRoleSetStmt *stmt)
{
    HeapTuple   roletuple;
    Form_pg_authid roleform;
    Oid         databaseid = InvalidOid;
    Oid         roleid = InvalidOid;
 
    if (stmt->role)
    {
        check_rolespec_name(stmt->role,
                            _("Cannot alter reserved roles."));
 
        roletuple = get_rolespec_tuple(stmt->role);
        roleform = (Form_pg_authid) GETSTRUCT(roletuple);
        roleid = roleform->oid;
 
        /*
         * Obtain a lock on the role and make sure it didn't go away in the
         * meantime.
         */
        shdepLockAndCheckObject(AuthIdRelationId, roleid);
 
        /*
         * To mess with a superuser you gotta be superuser; else you need
         * createrole, or just want to change your own settings
         */
        if (roleform->rolsuper)
        {
            if (!superuser())
                ereport(ERROR,
                        (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                         errmsg("must be superuser to alter superusers")));
        }
        else
        {
            if (!have_createrole_privilege() && roleid != GetUserId())
                ereport(ERROR,
                        (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                         errmsg("permission denied")));
        }
 
        ReleaseSysCache(roletuple);
    }
 
    /* look up and lock the database, if specified */
    if (stmt->database != NULL)
    {
        databaseid = get_database_oid(stmt->database, false);
        shdepLockAndCheckObject(DatabaseRelationId, databaseid);
 
        if (!stmt->role)
        {
            /*
             * If no role is specified, then this is effectively the same as
             * ALTER DATABASE ... SET, so use the same permission check.
             */
            if (!object_ownercheck(DatabaseRelationId, databaseid, GetUserId()))
                aclcheck_error(ACLCHECK_NOT_OWNER, OBJECT_DATABASE,
                               stmt->database);
        }
    }
 
    if (!stmt->role && !stmt->database)
    {
        /* Must be superuser to alter settings globally. */
        if (!superuser())
            ereport(ERROR,
                    (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                     errmsg("must be superuser to alter settings globally")));
    }
 
    AlterSetting(databaseid, roleid, stmt->setstmt);
 
    return roleid;
}
 
 
/*
 * DROP ROLE
 */
void
DropRole(DropRoleStmt *stmt)
{
    Relation    pg_authid_rel,
                pg_auth_members_rel;
    ListCell   *item;
    List       *role_addresses = NIL;
 
    if (!have_createrole_privilege())
        ereport(ERROR,
                (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                 errmsg("permission denied to drop role")));
 
    /*
     * Scan the pg_authid relation to find the Oid of the role(s) to be
     * deleted and perform preliminary permissions and sanity checks.
     */
    pg_authid_rel = table_open(AuthIdRelationId, RowExclusiveLock);
    pg_auth_members_rel = table_open(AuthMemRelationId, RowExclusiveLock);
 
    foreach(item, stmt->roles)
    {
        RoleSpec   *rolspec = lfirst(item);
        char       *role;
        HeapTuple   tuple,
                    tmp_tuple;
        Form_pg_authid roleform;
        ScanKeyData scankey;
        SysScanDesc sscan;
        Oid         roleid;
        ObjectAddress *role_address;
 
        if (rolspec->roletype != ROLESPEC_CSTRING)
            ereport(ERROR,
                    (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                     errmsg("cannot use special role specifier in DROP ROLE")));
        role = rolspec->rolename;
 
        tuple = SearchSysCache1(AUTHNAME, PointerGetDatum(role));
        if (!HeapTupleIsValid(tuple))
        {
            if (!stmt->missing_ok)
            {
                ereport(ERROR,
                        (errcode(ERRCODE_UNDEFINED_OBJECT),
                         errmsg("role \"%s\" does not exist", role)));
            }
            else
            {
                ereport(NOTICE,
                        (errmsg("role \"%s\" does not exist, skipping",
                                role)));
            }
 
            continue;
        }
 
        roleform = (Form_pg_authid) GETSTRUCT(tuple);
        roleid = roleform->oid;
 
        if (roleid == GetUserId())
            ereport(ERROR,
                    (errcode(ERRCODE_OBJECT_IN_USE),
                     errmsg("current user cannot be dropped")));
        if (roleid == GetOuterUserId())
            ereport(ERROR,
                    (errcode(ERRCODE_OBJECT_IN_USE),
                     errmsg("current user cannot be dropped")));
        if (roleid == GetSessionUserId())
            ereport(ERROR,
                    (errcode(ERRCODE_OBJECT_IN_USE),
                     errmsg("session user cannot be dropped")));
 
        /*
         * For safety's sake, we allow createrole holders to drop ordinary
         * roles but not superuser roles.  This is mainly to avoid the
         * scenario where you accidentally drop the last superuser.
         */
        if (roleform->rolsuper && !superuser())
            ereport(ERROR,
                    (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                     errmsg("must be superuser to drop superusers")));
 
        /* DROP hook for the role being removed */
        InvokeObjectDropHook(AuthIdRelationId, roleid, 0);
 
        /* Don't leak the syscache tuple */
        ReleaseSysCache(tuple);
 
        /*
         * Lock the role, so nobody can add dependencies to her while we drop
         * her.  We keep the lock until the end of transaction.
         */
        LockSharedObject(AuthIdRelationId, roleid, 0, AccessExclusiveLock);
 
        /*
         * If there is a pg_auth_members entry that has one of the roles to be
         * dropped as the roleid or member, it should be silently removed, but
         * if there is a pg_auth_members entry that has one of the roles to be
         * dropped as the grantor, the operation should fail.
         *
         * It's possible, however, that a single pg_auth_members entry could
         * fall into multiple categories - e.g. the user could do "GRANT foo
         * TO bar GRANTED BY baz" and then "DROP ROLE baz, bar". We want such
         * an operation to succeed regardless of the order in which the
         * to-be-dropped roles are passed to DROP ROLE.
         *
         * To make that work, we remove all pg_auth_members entries that can
         * be silently removed in this loop, and then below we'll make a
         * second pass over the list of roles to be removed and check for any
         * remaining dependencies.
         */
        ScanKeyInit(&scankey,
                    Anum_pg_auth_members_roleid,
                    BTEqualStrategyNumber, F_OIDEQ,
                    ObjectIdGetDatum(roleid));
 
        sscan = systable_beginscan(pg_auth_members_rel, AuthMemRoleMemIndexId,
                                   true, NULL, 1, &scankey);
 
        while (HeapTupleIsValid(tmp_tuple = systable_getnext(sscan)))
        {
            Form_pg_auth_members authmem_form;
 
            authmem_form = (Form_pg_auth_members) GETSTRUCT(tmp_tuple);
            deleteSharedDependencyRecordsFor(AuthMemRelationId,
                                             authmem_form->oid, 0);
            CatalogTupleDelete(pg_auth_members_rel, &tmp_tuple->t_self);
        }
 
        systable_endscan(sscan);
 
        ScanKeyInit(&scankey,
                    Anum_pg_auth_members_member,
                    BTEqualStrategyNumber, F_OIDEQ,
                    ObjectIdGetDatum(roleid));
 
        sscan = systable_beginscan(pg_auth_members_rel, AuthMemMemRoleIndexId,
                                   true, NULL, 1, &scankey);
 
        while (HeapTupleIsValid(tmp_tuple = systable_getnext(sscan)))
        {
            Form_pg_auth_members authmem_form;
 
            authmem_form = (Form_pg_auth_members) GETSTRUCT(tmp_tuple);
            deleteSharedDependencyRecordsFor(AuthMemRelationId,
                                             authmem_form->oid, 0);
            CatalogTupleDelete(pg_auth_members_rel, &tmp_tuple->t_self);
        }
 
        systable_endscan(sscan);
 
        /*
         * Advance command counter so that later iterations of this loop will
         * see the changes already made.  This is essential if, for example,
         * we are trying to drop both a role and one of its direct members ---
         * we'll get an error if we try to delete the linking pg_auth_members
         * tuple twice.  (We do not need a CCI between the two delete loops
         * above, because it's not allowed for a role to directly contain
         * itself.)
         */
        CommandCounterIncrement();
 
        /* Looks tentatively OK, add it to the list. */
        role_address = palloc(sizeof(ObjectAddress));
        role_address->classId = AuthIdRelationId;
        role_address->objectId = roleid;
        role_address->objectSubId = 0;
        role_addresses = lappend(role_addresses, role_address);
    }
 
    /*
     * Second pass over the roles to be removed.
     */
    foreach(item, role_addresses)
    {
        ObjectAddress *role_address = lfirst(item);
        Oid         roleid = role_address->objectId;
        HeapTuple   tuple;
        Form_pg_authid roleform;
        char       *detail;
        char       *detail_log;
 
        /*
         * Re-find the pg_authid tuple.
         *
         * Since we've taken a lock on the role OID, it shouldn't be possible
         * for the tuple to have been deleted -- or for that matter updated --
         * unless the user is manually modifying the system catalogs.
         */
        tuple = SearchSysCache1(AUTHOID, ObjectIdGetDatum(roleid));
        if (!HeapTupleIsValid(tuple))
            elog(ERROR, "could not find tuple for role %u", roleid);
        roleform = (Form_pg_authid) GETSTRUCT(tuple);
 
        /*
         * Check for pg_shdepend entries depending on this role.
         *
         * This needs to happen after we've completed removing any
         * pg_auth_members entries that can be removed silently, in order to
         * avoid spurious failures. See notes above for more details.
         */
        if (checkSharedDependencies(AuthIdRelationId, roleid,
                                    &detail, &detail_log))
            ereport(ERROR,
                    (errcode(ERRCODE_DEPENDENT_OBJECTS_STILL_EXIST),
                     errmsg("role \"%s\" cannot be dropped because some objects depend on it",
                            NameStr(roleform->rolname)),
                     errdetail_internal("%s", detail),
                     errdetail_log("%s", detail_log)));
 
        /*
         * Remove the role from the pg_authid table
         */
        CatalogTupleDelete(pg_authid_rel, &tuple->t_self);
 
        ReleaseSysCache(tuple);
 
        /*
         * Remove any comments or security labels on this role.
         */
        DeleteSharedComments(roleid, AuthIdRelationId);
        DeleteSharedSecurityLabel(roleid, AuthIdRelationId);
 
        /*
         * Remove settings for this role.
         */
        DropSetting(InvalidOid, roleid);
    }
 
    /*
     * Now we can clean up; but keep locks until commit.
     */
    table_close(pg_auth_members_rel, NoLock);
    table_close(pg_authid_rel, NoLock);
}
 
/*
 * Rename role
 */
ObjectAddress
RenameRole(const char *oldname, const char *newname)
{
    HeapTuple   oldtuple,
                newtuple;
    TupleDesc   dsc;
    Relation    rel;
    Datum       datum;
    bool        isnull;
    Datum       repl_val[Natts_pg_authid];
    bool        repl_null[Natts_pg_authid];
    bool        repl_repl[Natts_pg_authid];
    int         i;
    Oid         roleid;
    ObjectAddress address;
    Form_pg_authid authform;
 
    rel = table_open(AuthIdRelationId, RowExclusiveLock);
    dsc = RelationGetDescr(rel);
 
    oldtuple = SearchSysCache1(AUTHNAME, CStringGetDatum(oldname));
    if (!HeapTupleIsValid(oldtuple))
        ereport(ERROR,
                (errcode(ERRCODE_UNDEFINED_OBJECT),
                 errmsg("role \"%s\" does not exist", oldname)));
 
    /*
     * XXX Client applications probably store the session user somewhere, so
     * renaming it could cause confusion.  On the other hand, there may not be
     * an actual problem besides a little confusion, so think about this and
     * decide.  Same for SET ROLE ... we don't restrict renaming the current
     * effective userid, though.
     */
 
    authform = (Form_pg_authid) GETSTRUCT(oldtuple);
    roleid = authform->oid;
 
    if (roleid == GetSessionUserId())
        ereport(ERROR,
                (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                 errmsg("session user cannot be renamed")));
    if (roleid == GetOuterUserId())
        ereport(ERROR,
                (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                 errmsg("current user cannot be renamed")));
 
    /*
     * Check that the user is not trying to rename a system role and not
     * trying to rename a role into the reserved "pg_" namespace.
     */
    if (IsReservedName(NameStr(authform->rolname)))
        ereport(ERROR,
                (errcode(ERRCODE_RESERVED_NAME),
                 errmsg("role name \"%s\" is reserved",
                        NameStr(authform->rolname)),
                 errdetail("Role names starting with \"pg_\" are reserved.")));
 
    if (IsReservedName(newname))
        ereport(ERROR,
                (errcode(ERRCODE_RESERVED_NAME),
                 errmsg("role name \"%s\" is reserved",
                        newname),
                 errdetail("Role names starting with \"pg_\" are reserved.")));
 
    /*
     * If built with appropriate switch, whine when regression-testing
     * conventions for role names are violated.
     */
#ifdef ENFORCE_REGRESSION_TEST_NAME_RESTRICTIONS
    if (strncmp(newname, "regress_", 8) != 0)
        elog(WARNING, "roles created by regression test cases should have names starting with \"regress_\"");
#endif
 
    /* make sure the new name doesn't exist */
    if (SearchSysCacheExists1(AUTHNAME, CStringGetDatum(newname)))
        ereport(ERROR,
                (errcode(ERRCODE_DUPLICATE_OBJECT),
                 errmsg("role \"%s\" already exists", newname)));
 
    /*
     * createrole is enough privilege unless you want to mess with a superuser
     */
    if (((Form_pg_authid) GETSTRUCT(oldtuple))->rolsuper)
    {
        if (!superuser())
            ereport(ERROR,
                    (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                     errmsg("must be superuser to rename superusers")));
    }
    else
    {
        if (!have_createrole_privilege())
            ereport(ERROR,
                    (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                     errmsg("permission denied to rename role")));
    }
 
    /* OK, construct the modified tuple */
    for (i = 0; i < Natts_pg_authid; i++)
        repl_repl[i] = false;
 
    repl_repl[Anum_pg_authid_rolname - 1] = true;
    repl_val[Anum_pg_authid_rolname - 1] = DirectFunctionCall1(namein,
                                                               CStringGetDatum(newname));
    repl_null[Anum_pg_authid_rolname - 1] = false;
 
    datum = heap_getattr(oldtuple, Anum_pg_authid_rolpassword, dsc, &isnull);
 
    if (!isnull && get_password_type(TextDatumGetCString(datum)) == PASSWORD_TYPE_MD5)
    {
        /* MD5 uses the username as salt, so just clear it on a rename */
        repl_repl[Anum_pg_authid_rolpassword - 1] = true;
        repl_null[Anum_pg_authid_rolpassword - 1] = true;
 
        ereport(NOTICE,
                (errmsg("MD5 password cleared because of role rename")));
    }
 
    newtuple = heap_modify_tuple(oldtuple, dsc, repl_val, repl_null, repl_repl);
    CatalogTupleUpdate(rel, &oldtuple->t_self, newtuple);
 
    InvokeObjectPostAlterHook(AuthIdRelationId, roleid, 0);
 
    ObjectAddressSet(address, AuthIdRelationId, roleid);
 
    ReleaseSysCache(oldtuple);
 
    /*
     * Close pg_authid, but keep lock till commit.
     */
    table_close(rel, NoLock);
 
    return address;
}
 
/*
 * GrantRoleStmt
 *
 * Grant/Revoke roles to/from roles
 */
void
GrantRole(ParseState *pstate, GrantRoleStmt *stmt)
{
    Relation    pg_authid_rel;
    Oid         grantor;
    List       *grantee_ids;
    ListCell   *item;
    GrantRoleOptions    popt;
 
    /* Parse options list. */
    InitGrantRoleOptions(&popt);
    foreach(item, stmt->opt)
    {
        DefElem    *opt = (DefElem *) lfirst(item);
        char       *optval = defGetString(opt);
 
        if (strcmp(opt->defname, "admin") == 0)
        {
            popt.specified |= GRANT_ROLE_SPECIFIED_ADMIN;
 
            if (parse_bool(optval, &popt.admin))
                continue;
        }
        else if (strcmp(opt->defname, "inherit") == 0)
        {
            popt.specified |= GRANT_ROLE_SPECIFIED_INHERIT;
            if (parse_bool(optval, &popt.inherit))
                continue;
        }
        else if (strcmp(opt->defname, "set") == 0)
        {
            popt.specified |= GRANT_ROLE_SPECIFIED_SET;
            if (parse_bool(optval, &popt.set))
                continue;
        }
        else
            ereport(ERROR,
                    errcode(ERRCODE_SYNTAX_ERROR),
                    errmsg("unrecognized role option \"%s\"", opt->defname),
                    parser_errposition(pstate, opt->location));
 
        ereport(ERROR,
                (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                 errmsg("unrecognized value for role option \"%s\": \"%s\"",
                        opt->defname, optval),
                 parser_errposition(pstate, opt->location)));
    }
 
    /* Lookup OID of grantor, if specified. */
    if (stmt->grantor)
        grantor = get_rolespec_oid(stmt->grantor, false);
    else
        grantor = InvalidOid;
 
    grantee_ids = roleSpecsToIds(stmt->grantee_roles);
 
    /* AccessShareLock is enough since we aren't modifying pg_authid */
    pg_authid_rel = table_open(AuthIdRelationId, AccessShareLock);
 
    /*
     * Step through all of the granted roles and add, update, or remove
     * entries in pg_auth_members as appropriate. If stmt->is_grant is true,
     * we are adding new grants or, if they already exist, updating options
     * on those grants. If stmt->is_grant is false, we are revoking grants or
     * removing options from them.
     */
    foreach(item, stmt->granted_roles)
    {
        AccessPriv *priv = (AccessPriv *) lfirst(item);
        char       *rolename = priv->priv_name;
        Oid         roleid;
 
        /* Must reject priv(columns) and ALL PRIVILEGES(columns) */
        if (rolename == NULL || priv->cols != NIL)
            ereport(ERROR,
                    (errcode(ERRCODE_INVALID_GRANT_OPERATION),
                     errmsg("column names cannot be included in GRANT/REVOKE ROLE")));
 
        roleid = get_role_oid(rolename, false);
        if (stmt->is_grant)
            AddRoleMems(rolename, roleid,
                        stmt->grantee_roles, grantee_ids,
                        grantor, &popt);
        else
            DelRoleMems(rolename, roleid,
                        stmt->grantee_roles, grantee_ids,
                        grantor, &popt, stmt->behavior);
    }
 
    /*
     * Close pg_authid, but keep lock till commit.
     */
    table_close(pg_authid_rel, NoLock);
}
 
/*
 * DropOwnedObjects
 *
 * Drop the objects owned by a given list of roles.
 */
void
DropOwnedObjects(DropOwnedStmt *stmt)
{
    List       *role_ids = roleSpecsToIds(stmt->roles);
    ListCell   *cell;
 
    /* Check privileges */
    foreach(cell, role_ids)
    {
        Oid         roleid = lfirst_oid(cell);
 
        if (!has_privs_of_role(GetUserId(), roleid))
            ereport(ERROR,
                    (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                     errmsg("permission denied to drop objects")));
    }
 
    /* Ok, do it */
    shdepDropOwned(role_ids, stmt->behavior);
}
 
/*
 * ReassignOwnedObjects
 *
 * Give the objects owned by a given list of roles away to another user.
 */
void
ReassignOwnedObjects(ReassignOwnedStmt *stmt)
{
    List       *role_ids = roleSpecsToIds(stmt->roles);
    ListCell   *cell;
    Oid         newrole;
 
    /* Check privileges */
    foreach(cell, role_ids)
    {
        Oid         roleid = lfirst_oid(cell);
 
        if (!has_privs_of_role(GetUserId(), roleid))
            ereport(ERROR,
                    (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                     errmsg("permission denied to reassign objects")));
    }
 
    /* Must have privileges on the receiving side too */
    newrole = get_rolespec_oid(stmt->newrole, false);
 
    if (!has_privs_of_role(GetUserId(), newrole))
        ereport(ERROR,
                (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                 errmsg("permission denied to reassign objects")));
 
    /* Ok, do it */
    shdepReassignOwned(role_ids, newrole);
}
 
/*
 * roleSpecsToIds
 *
 * Given a list of RoleSpecs, generate a list of role OIDs in the same order.
 *
 * ROLESPEC_PUBLIC is not allowed.
 */
List *
roleSpecsToIds(List *memberNames)
{
    List       *result = NIL;
    ListCell   *l;
 
    foreach(l, memberNames)
    {
        RoleSpec   *rolespec = lfirst_node(RoleSpec, l);
        Oid         roleid;
 
        roleid = get_rolespec_oid(rolespec, false);
        result = lappend_oid(result, roleid);
    }
    return result;
}
 
/*
 * AddRoleMems -- Add given members to the specified role
 *
 * rolename: name of role to add to (used only for error messages)
 * roleid: OID of role to add to
 * memberSpecs: list of RoleSpec of roles to add (used only for error messages)
 * memberIds: OIDs of roles to add
 * grantorId: who is granting the membership (InvalidOid if not set explicitly)
 * popt: information about grant options
 */
static void
AddRoleMems(const char *rolename, Oid roleid,
            List *memberSpecs, List *memberIds,
            Oid grantorId, GrantRoleOptions *popt)
{
    Relation    pg_authmem_rel;
    TupleDesc   pg_authmem_dsc;
    ListCell   *specitem;
    ListCell   *iditem;
    Oid         currentUserId = GetUserId();
 
    Assert(list_length(memberSpecs) == list_length(memberIds));
 
    /* Skip permission check if nothing to do */
    if (!memberIds)
        return;
 
    /*
     * Check permissions: must have createrole or admin option on the role to
     * be changed.  To mess with a superuser role, you gotta be superuser.
     */
    if (superuser_arg(roleid))
    {
        if (!superuser())
            ereport(ERROR,
                    (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                     errmsg("must be superuser to alter superusers")));
    }
    else
    {
        if (!have_createrole_privilege() &&
            !is_admin_of_role(currentUserId, roleid))
            ereport(ERROR,
                    (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                     errmsg("must have admin option on role \"%s\"",
                            rolename)));
    }
 
    /*
     * The charter of pg_database_owner is to have exactly one, implicit,
     * situation-dependent member.  There's no technical need for this
     * restriction.  (One could lift it and take the further step of making
     * object_ownercheck(DatabaseRelationId, ...) equivalent to has_privs_of_role(roleid,
     * ROLE_PG_DATABASE_OWNER), in which case explicit, situation-independent
     * members could act as the owner of any database.)
     */
    if (roleid == ROLE_PG_DATABASE_OWNER)
        ereport(ERROR,
                errmsg("role \"%s\" cannot have explicit members", rolename));
 
    /* Validate grantor (and resolve implicit grantor if not specified). */
    grantorId = check_role_grantor(currentUserId, roleid, grantorId, true);
 
    pg_authmem_rel = table_open(AuthMemRelationId, RowExclusiveLock);
    pg_authmem_dsc = RelationGetDescr(pg_authmem_rel);
 
    /*
     * Only allow changes to this role by one backend at a time, so that we
     * can check integrity constraints like the lack of circular ADMIN OPTION
     * grants without fear of race conditions.
     */
    LockSharedObject(AuthIdRelationId, roleid, 0,
                     ShareUpdateExclusiveLock);
 
    /* Preliminary sanity checks. */
    forboth(specitem, memberSpecs, iditem, memberIds)
    {
        RoleSpec   *memberRole = lfirst_node(RoleSpec, specitem);
        Oid         memberid = lfirst_oid(iditem);
 
        /*
         * pg_database_owner is never a role member.  Lifting this restriction
         * would require a policy decision about membership loops.  One could
         * prevent loops, which would include making "ALTER DATABASE x OWNER
         * TO proposed_datdba" fail if is_member_of_role(pg_database_owner,
         * proposed_datdba).  Hence, gaining a membership could reduce what a
         * role could do.  Alternately, one could allow these memberships to
         * complete loops.  A role could then have actual WITH ADMIN OPTION on
         * itself, prompting a decision about is_admin_of_role() treatment of
         * the case.
         *
         * Lifting this restriction also has policy implications for ownership
         * of shared objects (databases and tablespaces).  We allow such
         * ownership, but we might find cause to ban it in the future.
         * Designing such a ban would more troublesome if the design had to
         * address pg_database_owner being a member of role FOO that owns a
         * shared object.  (The effect of such ownership is that any owner of
         * another database can act as the owner of affected shared objects.)
         */
        if (memberid == ROLE_PG_DATABASE_OWNER)
            ereport(ERROR,
                    errmsg("role \"%s\" cannot be a member of any role",
                           get_rolespec_name(memberRole)));
 
        /*
         * Refuse creation of membership loops, including the trivial case
         * where a role is made a member of itself.  We do this by checking to
         * see if the target role is already a member of the proposed member
         * role.  We have to ignore possible superuserness, however, else we
         * could never grant membership in a superuser-privileged role.
         */
        if (is_member_of_role_nosuper(roleid, memberid))
            ereport(ERROR,
                    (errcode(ERRCODE_INVALID_GRANT_OPERATION),
                     errmsg("role \"%s\" is a member of role \"%s\"",
                            rolename, get_rolespec_name(memberRole))));
    }
 
    /*
     * Disallow attempts to grant ADMIN OPTION back to a user who granted it
     * to you, similar to what check_circularity does for ACLs. We want the
     * chains of grants to remain acyclic, so that it's always possible to use
     * REVOKE .. CASCADE to clean up all grants that depend on the one being
     * revoked.
     *
     * NB: This check might look redundant with the check for membership loops
     * above, but it isn't. That's checking for role-member loop (e.g. A is a
     * member of B and B is a member of A) while this is checking for a
     * member-grantor loop (e.g. A gave ADMIN OPTION on X to B and now B, who
     * has no other source of ADMIN OPTION on X, tries to give ADMIN OPTION on
     * X back to A).
     */
    if (popt->admin && grantorId != BOOTSTRAP_SUPERUSERID)
    {
        CatCList   *memlist;
        RevokeRoleGrantAction *actions;
        int         i;
 
        /* Get the list of members for this role. */
        memlist = SearchSysCacheList1(AUTHMEMROLEMEM,
                                      ObjectIdGetDatum(roleid));
 
        /*
         * Figure out what would happen if we removed all existing grants to
         * every role to which we've been asked to make a new grant.
         */
        actions = initialize_revoke_actions(memlist);
        foreach(iditem, memberIds)
        {
            Oid         memberid = lfirst_oid(iditem);
 
            if (memberid == BOOTSTRAP_SUPERUSERID)
                ereport(ERROR,
                        (errcode(ERRCODE_INVALID_GRANT_OPERATION),
                         errmsg("admin option cannot be granted back to your own grantor")));
            plan_member_revoke(memlist, actions, memberid);
        }
 
        /*
         * If the result would be that the grantor role would no longer have
         * the ability to perform the grant, then the proposed grant would
         * create a circularity.
         */
        for (i = 0; i < memlist->n_members; ++i)
        {
            HeapTuple   authmem_tuple;
            Form_pg_auth_members authmem_form;
 
            authmem_tuple = &memlist->members[i]->tuple;
            authmem_form = (Form_pg_auth_members) GETSTRUCT(authmem_tuple);
 
            if (actions[i] == RRG_NOOP &&
                authmem_form->member == grantorId &&
                authmem_form->admin_option)
                break;
        }
        if (i >= memlist->n_members)
            ereport(ERROR,
                    (errcode(ERRCODE_INVALID_GRANT_OPERATION),
                     errmsg("admin option cannot be granted back to your own grantor")));
 
        ReleaseSysCacheList(memlist);
    }
 
    /* Now perform the catalog updates. */
    forboth(specitem, memberSpecs, iditem, memberIds)
    {
        RoleSpec   *memberRole = lfirst_node(RoleSpec, specitem);
        Oid         memberid = lfirst_oid(iditem);
        HeapTuple   authmem_tuple;
        HeapTuple   tuple;
        Datum       new_record[Natts_pg_auth_members] = {0};
        bool        new_record_nulls[Natts_pg_auth_members] = {0};
        bool        new_record_repl[Natts_pg_auth_members] = {0};
 
        /* Common initialization for possible insert or update */
        new_record[Anum_pg_auth_members_roleid - 1] =
            ObjectIdGetDatum(roleid);
        new_record[Anum_pg_auth_members_member - 1] =
            ObjectIdGetDatum(memberid);
        new_record[Anum_pg_auth_members_grantor - 1] =
            ObjectIdGetDatum(grantorId);
 
        /* Find any existing tuple */
        authmem_tuple = SearchSysCache3(AUTHMEMROLEMEM,
                                        ObjectIdGetDatum(roleid),
                                        ObjectIdGetDatum(memberid),
                                        ObjectIdGetDatum(grantorId));
 
        /*
         * If we found a tuple, update it with new option values, unless
         * there are no changes, in which case issue a WARNING.
         *
         * If we didn't find a tuple, just insert one.
         */
        if (HeapTupleIsValid(authmem_tuple))
        {
            Form_pg_auth_members authmem_form;
            bool        at_least_one_change = false;
 
            authmem_form = (Form_pg_auth_members) GETSTRUCT(authmem_tuple);
 
            if ((popt->specified & GRANT_ROLE_SPECIFIED_ADMIN) != 0
                && authmem_form->admin_option != popt->admin)
            {
                new_record[Anum_pg_auth_members_admin_option - 1] =
                    BoolGetDatum(popt->admin);
                new_record_repl[Anum_pg_auth_members_admin_option - 1] =
                    true;
                at_least_one_change = true;
            }
 
            if ((popt->specified & GRANT_ROLE_SPECIFIED_INHERIT) != 0
                && authmem_form->inherit_option != popt->inherit)
            {
                new_record[Anum_pg_auth_members_inherit_option - 1] =
                    BoolGetDatum(popt->inherit);
                new_record_repl[Anum_pg_auth_members_inherit_option - 1] =
                    true;
                at_least_one_change = true;
            }
 
            if ((popt->specified & GRANT_ROLE_SPECIFIED_SET) != 0
                && authmem_form->set_option != popt->set)
            {
                new_record[Anum_pg_auth_members_set_option - 1] =
                    BoolGetDatum(popt->set);
                new_record_repl[Anum_pg_auth_members_set_option - 1] =
                    true;
                at_least_one_change = true;
            }
 
            if (!at_least_one_change)
            {
                ereport(NOTICE,
                        (errmsg("role \"%s\" has already been granted membership in role \"%s\" by role \"%s\"",
                                get_rolespec_name(memberRole), rolename,
                                GetUserNameFromId(grantorId, false))));
                ReleaseSysCache(authmem_tuple);
                continue;
            }
 
            tuple = heap_modify_tuple(authmem_tuple, pg_authmem_dsc,
                                      new_record,
                                      new_record_nulls, new_record_repl);
            CatalogTupleUpdate(pg_authmem_rel, &tuple->t_self, tuple);
 
            ReleaseSysCache(authmem_tuple);
        }
        else
        {
            Oid         objectId;
            Oid        *newmembers = palloc(sizeof(Oid));
 
            /*
             * The values for these options can be taken directly from 'popt'.
             * Either they were specified, or the defaults as set by
             * InitGrantRoleOptions are correct.
             */
            new_record[Anum_pg_auth_members_admin_option - 1] =
                BoolGetDatum(popt->admin);
            new_record[Anum_pg_auth_members_set_option - 1] =
                BoolGetDatum(popt->set);
 
            /*
             * If the user specified a value for the inherit option, use
             * whatever was specified. Otherwise, set the default value based
             * on the role-level property.
             */
            if ((popt->specified & GRANT_ROLE_SPECIFIED_INHERIT) != 0)
                new_record[Anum_pg_auth_members_inherit_option - 1] =
                    popt->inherit;
            else
            {
                HeapTuple       mrtup;
                Form_pg_authid  mrform;
 
                mrtup = SearchSysCache1(AUTHOID, memberid);
                if (!HeapTupleIsValid(mrtup))
                    elog(ERROR, "cache lookup failed for role %u", memberid);
                mrform = (Form_pg_authid) GETSTRUCT(mrtup);
                new_record[Anum_pg_auth_members_inherit_option - 1] =
                    mrform->rolinherit;
                ReleaseSysCache(mrtup);
            }
 
            /* get an OID for the new row and insert it */
            objectId = GetNewObjectId();
            new_record[Anum_pg_auth_members_oid - 1] = objectId;
            tuple = heap_form_tuple(pg_authmem_dsc,
                                    new_record, new_record_nulls);
            CatalogTupleInsert(pg_authmem_rel, tuple);
 
            /* updateAclDependencies wants to pfree array inputs */
            newmembers[0] = grantorId;
            updateAclDependencies(AuthMemRelationId, objectId,
                                  0, InvalidOid,
                                  0, NULL,
                                  1, newmembers);
        }
 
        /* CCI after each change, in case there are duplicates in list */
        CommandCounterIncrement();
    }
 
    /*
     * Close pg_authmem, but keep lock till commit.
     */
    table_close(pg_authmem_rel, NoLock);
}
 
/*
 * DelRoleMems -- Remove given members from the specified role
 *
 * rolename: name of role to del from (used only for error messages)
 * roleid: OID of role to del from
 * memberSpecs: list of RoleSpec of roles to del (used only for error messages)
 * memberIds: OIDs of roles to del
 * grantorId: who is revoking the membership
 * popt: information about grant options
 * behavior: RESTRICT or CASCADE behavior for recursive removal
 */
static void
DelRoleMems(const char *rolename, Oid roleid,
            List *memberSpecs, List *memberIds,
            Oid grantorId, GrantRoleOptions *popt, DropBehavior behavior)
{
    Relation    pg_authmem_rel;
    TupleDesc   pg_authmem_dsc;
    ListCell   *specitem;
    ListCell   *iditem;
    Oid         currentUserId = GetUserId();
    CatCList   *memlist;
    RevokeRoleGrantAction *actions;
    int         i;
 
    Assert(list_length(memberSpecs) == list_length(memberIds));
 
    /* Skip permission check if nothing to do */
    if (!memberIds)
        return;
 
    /*
     * Check permissions: must have createrole or admin option on the role to
     * be changed.  To mess with a superuser role, you gotta be superuser.
     */
    if (superuser_arg(roleid))
    {
        if (!superuser())
            ereport(ERROR,
                    (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                     errmsg("must be superuser to alter superusers")));
    }
    else
    {
        if (!have_createrole_privilege() &&
            !is_admin_of_role(currentUserId, roleid))
            ereport(ERROR,
                    (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                     errmsg("must have admin option on role \"%s\"",
                            rolename)));
    }
 
    /* Validate grantor (and resolve implicit grantor if not specified). */
    grantorId = check_role_grantor(currentUserId, roleid, grantorId, false);
 
    pg_authmem_rel = table_open(AuthMemRelationId, RowExclusiveLock);
    pg_authmem_dsc = RelationGetDescr(pg_authmem_rel);
 
    /*
     * Only allow changes to this role by one backend at a time, so that we
     * can check for things like dependent privileges without fear of race
     * conditions.
     */
    LockSharedObject(AuthIdRelationId, roleid, 0,
                     ShareUpdateExclusiveLock);
 
    memlist = SearchSysCacheList1(AUTHMEMROLEMEM, ObjectIdGetDatum(roleid));
    actions = initialize_revoke_actions(memlist);
 
    /*
     * We may need to recurse to dependent privileges if DROP_CASCADE was
     * specified, or refuse to perform the operation if dependent privileges
     * exist and DROP_RESTRICT was specified. plan_single_revoke() will figure
     * out what to do with each catalog tuple.
     */
    forboth(specitem, memberSpecs, iditem, memberIds)
    {
        RoleSpec   *memberRole = lfirst(specitem);
        Oid         memberid = lfirst_oid(iditem);
 
        if (!plan_single_revoke(memlist, actions, memberid, grantorId,
                                popt, behavior))
        {
            ereport(WARNING,
                    (errmsg("role \"%s\" has not been granted membership in role \"%s\" by role \"%s\"",
                            get_rolespec_name(memberRole), rolename,
                            GetUserNameFromId(grantorId, false))));
            continue;
        }
    }
 
    /*
     * We now know what to do with each catalog tuple: it should either be
     * left alone, deleted, or just have the admin_option flag cleared.
     * Perform the appropriate action in each case.
     */
    for (i = 0; i < memlist->n_members; ++i)
    {
        HeapTuple   authmem_tuple;
        Form_pg_auth_members authmem_form;
 
        if (actions[i] == RRG_NOOP)
            continue;
 
        authmem_tuple = &memlist->members[i]->tuple;
        authmem_form = (Form_pg_auth_members) GETSTRUCT(authmem_tuple);
 
        if (actions[i] == RRG_DELETE_GRANT)
        {
            /*
             * Remove the entry altogether, after first removing its
             * dependencies
             */
            deleteSharedDependencyRecordsFor(AuthMemRelationId,
                                             authmem_form->oid, 0);
            CatalogTupleDelete(pg_authmem_rel, &authmem_tuple->t_self);
        }
        else
        {
            /* Just turn off the specified option */
            HeapTuple   tuple;
            Datum       new_record[Natts_pg_auth_members] = {0};
            bool        new_record_nulls[Natts_pg_auth_members] = {0};
            bool        new_record_repl[Natts_pg_auth_members] = {0};
 
            /* Build a tuple to update with */
            if (actions[i] == RRG_REMOVE_ADMIN_OPTION)
            {
                new_record[Anum_pg_auth_members_admin_option - 1] =
                    BoolGetDatum(false);
                new_record_repl[Anum_pg_auth_members_admin_option - 1] =
                    true;
            }
            else if (actions[i] == RRG_REMOVE_INHERIT_OPTION)
            {
                new_record[Anum_pg_auth_members_inherit_option - 1] =
                    BoolGetDatum(false);
                new_record_repl[Anum_pg_auth_members_inherit_option - 1] =
                    true;
            }
            else if (actions[i] == RRG_REMOVE_SET_OPTION)
            {
                new_record[Anum_pg_auth_members_set_option - 1] =
                    BoolGetDatum(false);
                new_record_repl[Anum_pg_auth_members_set_option - 1] =
                    true;
            }
            else
                elog(ERROR, "unknown role revoke action");
 
            tuple = heap_modify_tuple(authmem_tuple, pg_authmem_dsc,
                                      new_record,
                                      new_record_nulls, new_record_repl);
            CatalogTupleUpdate(pg_authmem_rel, &tuple->t_self, tuple);
        }
    }
 
    ReleaseSysCacheList(memlist);
 
    /*
     * Close pg_authmem, but keep lock till commit.
     */
    table_close(pg_authmem_rel, NoLock);
}
 
/*
 * Sanity-check, or infer, the grantor for a GRANT or REVOKE statement
 * targeting a role.
 *
 * The grantor must always be either a role with ADMIN OPTION on the role in
 * which membership is being granted, or the bootstrap superuser. This is
 * similar to the restriction enforced by select_best_grantor, except that
 * roles don't have owners, so we regard the bootstrap superuser as the
 * implicit owner.
 *
 * If the grantor was not explicitly specified by the user, grantorId should
 * be passed as InvalidOid, and this function will infer the user to be
 * recorded as the grantor. In many cases, this will be the current user, but
 * things get more complicated when the current user doesn't possess ADMIN
 * OPTION on the role but rather relies on having CREATEROLE privileges, or
 * on inheriting the privileges of a role which does have ADMIN OPTION. See
 * below for details.
 *
 * If the grantor was specified by the user, then it must be a user that
 * can legally be recorded as the grantor, as per the rule stated above.
 * This is an integrity constraint, not a permissions check, and thus even
 * superusers are subject to this restriction. However, there is also a
 * permissions check: to specify a role as the grantor, the current user
 * must possess the privileges of that role. Superusers will always pass
 * this check, but for non-superusers it may lead to an error.
 *
 * The return value is the OID to be regarded as the grantor when executing
 * the operation.
 */
static Oid
check_role_grantor(Oid currentUserId, Oid roleid, Oid grantorId, bool is_grant)
{
    /* If the grantor ID was not specified, pick one to use. */
    if (!OidIsValid(grantorId))
    {
        /*
         * Grants where the grantor is recorded as the bootstrap superuser do
         * not depend on any other existing grants, so always default to this
         * interpretation when possible.
         */
        if (has_createrole_privilege(currentUserId))
            return BOOTSTRAP_SUPERUSERID;
 
        /*
         * Otherwise, the grantor must either have ADMIN OPTION on the role or
         * inherit the privileges of a role which does. In the former case,
         * record the grantor as the current user; in the latter, pick one of
         * the roles that is "most directly" inherited by the current role
         * (i.e. fewest "hops").
         *
         * (We shouldn't fail to find a best grantor, because we've already
         * established that the current user has permission to perform the
         * operation.)
         */
        grantorId = select_best_admin(currentUserId, roleid);
        if (!OidIsValid(grantorId))
            elog(ERROR, "no possible grantors");
        return grantorId;
    }
 
    /*
     * If an explicit grantor is specified, it must be a role whose privileges
     * the current user possesses.
     *
     * It should also be a role that has ADMIN OPTION on the target role, but
     * we check this condition only in case of GRANT. For REVOKE, no matching
     * grant should exist anyway, but if it somehow does, let the user get rid
     * of it.
     */
    if (is_grant)
    {
        if (!has_privs_of_role(currentUserId, grantorId))
            ereport(ERROR,
                    (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                     errmsg("permission denied to grant privileges as role \"%s\"",
                            GetUserNameFromId(grantorId, false))));
 
        if (grantorId != BOOTSTRAP_SUPERUSERID &&
            select_best_admin(grantorId, roleid) != grantorId)
            ereport(ERROR,
                    (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                     errmsg("grantor must have ADMIN OPTION on \"%s\"",
                            GetUserNameFromId(roleid, false))));
    }
    else
    {
        if (!has_privs_of_role(currentUserId, grantorId))
            ereport(ERROR,
                    (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                     errmsg("permission denied to revoke privileges granted by role \"%s\"",
                            GetUserNameFromId(grantorId, false))));
    }
 
    /*
     * If a grantor was specified explicitly, always attribute the grant to
     * that role (unless we error out above).
     */
    return grantorId;
}
 
/*
 * Initialize an array of RevokeRoleGrantAction objects.
 *
 * 'memlist' should be a list of all grants for the target role.
 *
 * This constructs an array indicating that no actions are to be performed;
 * that is, every element is initially RRG_NOOP.
 */
static RevokeRoleGrantAction *
initialize_revoke_actions(CatCList *memlist)
{
    RevokeRoleGrantAction *result;
    int         i;
 
    if (memlist->n_members == 0)
        return NULL;
 
    result = palloc(sizeof(RevokeRoleGrantAction) * memlist->n_members);
    for (i = 0; i < memlist->n_members; i++)
        result[i] = RRG_NOOP;
    return result;
}
 
/*
 * Figure out what we would need to do in order to revoke a grant, or just the
 * admin option on a grant, given that there might be dependent privileges.
 *
 * 'memlist' should be a list of all grants for the target role.
 *
 * Whatever actions prove to be necessary will be signalled by updating
 * 'actions'.
 *
 * If behavior is DROP_RESTRICT, an error will occur if there are dependent
 * role membership grants; if DROP_CASCADE, those grants will be scheduled
 * for deletion.
 *
 * The return value is true if the matching grant was found in the list,
 * and false if not.
 */
static bool
plan_single_revoke(CatCList *memlist, RevokeRoleGrantAction *actions,
                   Oid member, Oid grantor, GrantRoleOptions *popt,
                   DropBehavior behavior)
{
    int         i;
 
    /*
     * If popt.specified == 0, we're revoking the grant entirely; otherwise,
     * we expect just one bit to be set, and we're revoking the corresponding
     * option. As of this writing, there's no syntax that would allow for
     * an attempt to revoke multiple options at once, and the logic below
     * wouldn't work properly if such syntax were added, so assert that our
     * caller isn't trying to do that.
     */
    Assert(pg_popcount32(popt->specified) <= 1);
 
    for (i = 0; i < memlist->n_members; ++i)
    {
        HeapTuple   authmem_tuple;
        Form_pg_auth_members authmem_form;
 
        authmem_tuple = &memlist->members[i]->tuple;
        authmem_form = (Form_pg_auth_members) GETSTRUCT(authmem_tuple);
 
        if (authmem_form->member == member &&
            authmem_form->grantor == grantor)
        {
            if ((popt->specified & GRANT_ROLE_SPECIFIED_INHERIT) != 0)
            {
                /*
                 * Revoking the INHERIT option doesn't change anything for
                 * dependent privileges, so we don't need to recurse.
                 */
                actions[i] = RRG_REMOVE_INHERIT_OPTION;
            }
            else if ((popt->specified & GRANT_ROLE_SPECIFIED_SET) != 0)
            {
                /* Here too, no need to recurse. */
                actions[i] = RRG_REMOVE_SET_OPTION;
            }
            else
            {
                bool    revoke_admin_option_only;
 
                /*
                 * Revoking the grant entirely, or ADMIN option on a grant,
                 * implicates dependent privileges, so we may need to recurse.
                 */
                revoke_admin_option_only =
                    (popt->specified & GRANT_ROLE_SPECIFIED_ADMIN) != 0;
                plan_recursive_revoke(memlist, actions, i,
                                      revoke_admin_option_only, behavior);
            }
            return true;
        }
    }
 
    return false;
}
 
/*
 * Figure out what we would need to do in order to revoke all grants to
 * a given member, given that there might be dependent privileges.
 *
 * 'memlist' should be a list of all grants for the target role.
 *
 * Whatever actions prove to be necessary will be signalled by updating
 * 'actions'.
 */
static void
plan_member_revoke(CatCList *memlist, RevokeRoleGrantAction *actions,
                   Oid member)
{
    int         i;
 
    for (i = 0; i < memlist->n_members; ++i)
    {
        HeapTuple   authmem_tuple;
        Form_pg_auth_members authmem_form;
 
        authmem_tuple = &memlist->members[i]->tuple;
        authmem_form = (Form_pg_auth_members) GETSTRUCT(authmem_tuple);
 
        if (authmem_form->member == member)
            plan_recursive_revoke(memlist, actions, i, false, DROP_CASCADE);
    }
}
 
/*
 * Workhorse for figuring out recursive revocation of role grants.
 *
 * This is similar to what recursive_revoke() does for ACLs.
 */
static void
plan_recursive_revoke(CatCList *memlist, RevokeRoleGrantAction *actions,
                      int index,
                      bool revoke_admin_option_only, DropBehavior behavior)
{
    bool        would_still_have_admin_option = false;
    HeapTuple   authmem_tuple;
    Form_pg_auth_members authmem_form;
    int         i;
 
    /* If it's already been done, we can just return. */
    if (actions[index] == RRG_DELETE_GRANT)
        return;
    if (actions[index] == RRG_REMOVE_ADMIN_OPTION &&
        revoke_admin_option_only)
        return;
 
    /* Locate tuple data. */
    authmem_tuple = &memlist->members[index]->tuple;
    authmem_form = (Form_pg_auth_members) GETSTRUCT(authmem_tuple);
 
    /*
     * If the existing tuple does not have admin_option set, then we do not
     * need to recurse. If we're just supposed to clear that bit we don't need
     * to do anything at all; if we're supposed to remove the grant, we need
     * to do something, but only to the tuple, and not any others.
     */
    if (!revoke_admin_option_only)
    {
        actions[index] = RRG_DELETE_GRANT;
        if (!authmem_form->admin_option)
            return;
    }
    else
    {
        if (!authmem_form->admin_option)
            return;
        actions[index] = RRG_REMOVE_ADMIN_OPTION;
    }
 
    /* Determine whether the member would still have ADMIN OPTION. */
    for (i = 0; i < memlist->n_members; ++i)
    {
        HeapTuple   am_cascade_tuple;
        Form_pg_auth_members am_cascade_form;
 
        am_cascade_tuple = &memlist->members[i]->tuple;
        am_cascade_form = (Form_pg_auth_members) GETSTRUCT(am_cascade_tuple);
 
        if (am_cascade_form->member == authmem_form->member &&
            am_cascade_form->admin_option && actions[i] == RRG_NOOP)
        {
            would_still_have_admin_option = true;
            break;
        }
    }
 
    /* If the member would still have ADMIN OPTION, we need not recurse. */
    if (would_still_have_admin_option)
        return;
 
    /*
     * Recurse to grants that are not yet slated for deletion which have this
     * member as the grantor.
     */
    for (i = 0; i < memlist->n_members; ++i)
    {
        HeapTuple   am_cascade_tuple;
        Form_pg_auth_members am_cascade_form;
 
        am_cascade_tuple = &memlist->members[i]->tuple;
        am_cascade_form = (Form_pg_auth_members) GETSTRUCT(am_cascade_tuple);
 
        if (am_cascade_form->grantor == authmem_form->member &&
            actions[i] != RRG_DELETE_GRANT)
        {
            if (behavior == DROP_RESTRICT)
                ereport(ERROR,
                        (errcode(ERRCODE_DEPENDENT_OBJECTS_STILL_EXIST),
                         errmsg("dependent privileges exist"),
                         errhint("Use CASCADE to revoke them too.")));
 
            plan_recursive_revoke(memlist, actions, i, false, behavior);
        }
    }
}
 
/*
 * Initialize a GrantRoleOptions object with default values.
 */
static void
InitGrantRoleOptions(GrantRoleOptions *popt)
{
    popt->specified = 0;
    popt->admin = false;
    popt->inherit = false;
    popt->set = true;
}